check your ground and power and speaker wires @ the amp... those being loose will also cause this

I did this already.
I'm going to take a multimeter to the subs and check that. Also I'm going to check to see if a cable came loose inside be box

did he re wire them? maybe down to 1 ohm? amp not 1 ohm stable?

Depending on the subwoofers and/or power hes running most subwoofers dont need break in I threw my 18" BTL on 2300w daily right out of the box same with my DC Level 3 15's and my Fi 15" SSD Fully Loaded. Some woofers like AudioCrap (audioque) require break in because they make their spiders rediculously hard.

they make the spiders stiff out of the box to make the overall lifespan longer.

same reason they use direct leads...its better in the long run.

although I love aq amps their subs need a little work.. dont get me wrong there loud but I wouldnt buy anything but hdc3 12s.. they can holdntheir own but any bigger they lack greatly